property-testing SKILL.md skillA
property-testing from nyxandro/property-testing-skill is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add nyxandro/property-testing-skill/property-testing@v1.0.0Pins v1.0.0 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- nyxandro/property-testing-skill
- Path
property-testing/SKILL.md- Versions recorded
- 3
- Latest version
- v1.0.0, committed Nov 5, 2026
- First version recorded
- Sep 13, 2026
- Size
- 21,312 bytes
- Repository stars
- 4
- License
- MIT
Property-based tests: fast-check with Vitest in TypeScript, Hypothesis with pytest in Python. Writes new property tests, exposes a property in code that seems to have none, reviews existing property tests for ones that assert nothing, and triages a failed property test into a wrong property, an ambiguous spec or a real bug. Use it when the owner asks for property tests or for inputs the existing tests miss: "write property tests for this parser", "find the edge cases this function misses…
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Property-based tests An example test checks the inputs someone thought of. A property test states what must hold for every input, lets the library generate hundreds of inputs it would take a person weeks to think of, and when one breaks the statement, shrinks it to the smallest case that still breaks it: not a list of three hundred elements but `[0]` with `n = 2`. That minimal case points at the bug directly. Property tests complement example tests, they do not replace them. One property test per function that has a clear property; everything else stays example-based. Do not convert existing example tests, do not add properties to glue code. Code with no property gets example tests, and saying so is a valid outcome. A green property test is not a proof. It says the generator found no counterexample in the runs it made, over the domain you described; it does not say none exists. Its strength is exactly the honesty of the generator. Report it that way: "no counterexample in a hundred runs over inputs of this shape", never "correct for all inputs". The method is the same in every language. The first part of this skill is the method; the two …
Read the whole file at its exact version.
How to install
mdr add nyxandro/property-testing-skill/property-testing@sha256:dd92c19e4b7cefb7The line at the top of this page pins the label v1.0.0, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_566o7jhlqmaq3ydt)
3 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Sep 13, 2026 and Nov 5, 2026, about one every 27 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| v1.0.0 latest | 2026-11-05 | 3f60a2c | 21,312 B | A | view · diff |
| git:20260913.786d52b | 2026-09-13 | 786d52b | 21,283 B | A | view · diff |
| git:20260913.6957adf | 2026-09-13 | 6957adf | 20,349 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (21312 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
nyxandro/property-testing-skill · 4 stars · license MIT · pushed 2026-11-05 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_566o7jhlqmaq3ydt GET https://markdownregistry.com/api/v1/resolve?ref=nyxandro/property-testing-skill/property-testing GET https://markdownregistry.com/api/v1/blob/dd92c19e4b7cefb76485f4e53f45c1b400352676d21acee348f6431c1ea4d57c
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.